Bell's inequality is important because it shows that quantum
mechanics predicts macroscopic violations of locality. This can
only be tested by suitable *macroscopic* measurements. To
discriminate between the class of theories we are proposing one
must use statistically irreversible macroscopic events to measure
the timing. If the probability of reversal is sufficiently low the
events can be treated as if they were absolutely irreversible. If
necessary their probability of being reversed can be factored into
the experimental analysis. Experimenters often implicitly assume
this criteria for the completion of an event even though it cannot
be justified in the formalism of quantum mechanics.

**Figure:** Typical experiment to test Bell's
inequality

Reported experiments generally involve a setup such as that
shown in Figure . Quantum
mechanics predicts that the correlation between joint detection
will change as a function of the polarizer (or other experimental
apparatus) settings with a delay given by the time it takes light
to travel the distance **L**. Most experiments are symmetric.
**L** is the distance from either polarizer to the
*closest* detector. Locality demands that a change large
enough to violate Bell's inequality can only happen in the time it
would take light to travel the longer distance **K**. **K**
is the distance from either polarizer to the *more distant*
detector. To show locality is violated one must show that the delay
(**D**) between when the polarizer settings are changed and the
correlations change is short enough that where **C** is the speed of light.

It is technically difficult to directly measure **D** and
none of the reported experiments do this. Indirect arguments about
**D** are all questionable. We have no idea what is happening
between the time the excited state was prepared and the two
detections occurred. Thus we can make no assumptions about what is
happening microscopically. This is true both because quantum
mechanics is silent on what is happening and because these
experiments are testing the correctness of quantum mechanics
itself.

To directly measure **D** requires that one have a high rate
of singlet state events or a common trigger that controls these
events and the change in polarizer angles. If this condition is not
met the delay we measure will be dominated by the uncertainty in
when a singlet state event occurs. After we change the parameter
settings the average delay we observe will be where **r** is the rate of singlet
state events and **D** is the delay we want to measure. If
it will be impossible
to accurately measure **D**. Typical experiments involve
distances of a few meters. This correspond to expected values of
ns. if locality holds
and **D < 1** ns. if quantum mechanics is correct. A high
rate of singlet state events or a precise common trigger for
singlet state events and changes in polarizer angles is necessary
to discriminate between these times.

To show a violation of Bell's inequality one must show the
superluminal transmission of information (at least by Shannon's
definition of information). One must show that a change in
polarizer angles changes the probability of joint detections in
less time than it would take light to travel from either detector
to the more distant analyzer. For this change to be sufficient to
violate Bell's inequality requires that information about *at
least one* (we cannot tell which one) polarizer setting
influenced the more distant detector. There must be a macroscopic
record to claim information has been transferred. It is the time of
that record that must be used in determining if the information
transfer was superluminal.

If one can show superluminal information transfer then one has a violation of relativistic locality (ignoring the predeterminism loophole) that is independent of the details of the experiment. Any attempt to enumerate and eliminate all loopholes is insufficient because one can never figure out all the ways that nature might out fox you.

It is worth noting that the historical roots of these
predictions is the assumption that the wave function changes
*instantaneously* when an observation occurs. This assumption
has been built into the mathematics of quantum mechanics in a way
that creates irreducibly nonlocal operations. Quantum mechanics
insists that there is no hidden mechanistic process that enforces
the conservation laws. It is this assumption that creates the
singlet state entanglement that enforces conservation laws
nonlocally as if by magic with no underlying mechanism.

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